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Spectroscopic properties and singlet oxygen production by the compound ethyl
Antonio Eduardo da Hora Machado1, Lucas Ferreira de Paula, Ana Maria Ferreira de Oliveira-Campos
1Universidade Federal de Uberlândia, Instituto de Química, Laboratório de Fotoquímica e Ciência de Materiais, P.O. Box 593, CEP 38400-902, Uberlândia, Minas Gerais, Brazil. aehmachado@gmail.com
Abstract:
The steady state and time resolved experiments together with absorption and emission spectroscopies and quantum chemical calculations have been employed to investigate spectroscopic properties of a xanthone-type compound (ethyl 3,12-dioxopyran[3,2-a]xanthone-2-carboxylate). The spectroscopic data show good agreement with results obtained from quantum chemical calculations. Additionally, this compound shows expressive quantum efficiency for triplet population and a quantum efficiency of singlet oxygen generation very close to unity. Correlations between the nature of singlet and triplet excited states and spectroscopic properties were performed in order to understand the high quantum efficiency of singlet oxygen generation by this compound.
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